Adsorbent for removing water vapor during corrosive gas purification and method for preparing the adsorbent

Abstract

Herein is disclosed a method for preparing an adsorbent to effectively remove water vapor during purification of a corrosive gas, as well as an adsorbent so prepared.

What is claimed is:  
     
         1 . A method of treating an adsorbent, comprising: 
 first heating the adsorbent at a first temperature under dry nitrogen; and    second heating the adsorbent at a second temperature, wherein the second temperature is less than the first temperature and greater than 100° C., under a gas comprising Cl 2 , Br 2 , F 2 , HCl, HF, or HBr.    
     
     
         2 . The method of  claim 1 , wherein the gas comprises Cl 2 .  
     
     
         3 . The method of  claim 1 , wherein the first temperature is from about 150° C. to about 350° C.  
     
     
         4 . The method of  claim 3 , wherein the first temperature is from about 300° C. to about 350° C., and the first heating is performed for from about 12 hr to about 72 hr.  
     
     
         5 . The method of  claim 1 , wherein the second temperature is from about 150° C. to about 250° C.  
     
     
         6 . The method of  claim 5 , wherein the second temperature is from about 175° C. to about 225° C., and the second heating is performed for from about 6 hr to about 48 hr.  
     
     
         7 . The method of  claim 1 , further comprising repeating the first heating and the second heating steps until CO 2  and water vapor are substantially not detectable in the nitrogen or the gas comprising Cl 2 , Br 2 , F 2 , HCl, HF, or HBr.  
     
     
         8 . The method of  claim 7 , wherein the gas comprises Cl 2 .  
     
     
         9 . An adsorbent, prepared by a method comprising: 
 first heating the adsorbent at a first temperature under dry nitrogen; and    second heating the adsorbent at a second temperature, wherein the second temperature is less than the first temperature and greater than 100° C., under a gas comprising Cl 2 , Br 2 , F 2 , HCl, HF, or HBr.    
     
     
         10 . The adsorbent of  claim 9 , wherein the gas comprises Cl 2 .  
     
     
         11 . The adsorbent of  claim 9 , wherein the method further comprises: 
 repeating the first heating and the second heating steps until CO 2  and water vapor are substantially not detectable in the nitrogen or the gas comprising Cl 2 , Br 2 , F 2 , HCl, HF, or HBr.    
     
     
         12 . The adsorbent of  claim 11 , wherein the gas comprises Cl 2 .  
     
     
         13 . The adsorbent of  claim 9 , wherein the adsorbent is a silica-alumina adsorbent, an alumina adsorbent, or an activated carbon adsorbent.  
     
     
         14 . The adsorbent of  claim 10 , wherein the adsorbent is a silica-alumina adsorbent.